(a) Field of the Invention
A cushion improved structure of shoe ventilating insole is a flexible insole which comprises a top insole having improved air inlet and outlet ports, a bottom insole and a middle smaller area foam pad, a raised face is integrally made on top of the heel area at the top surface of said top insole, and a plurality of air inlet ports are made at lower peripheral edge of said raised face, further, several grooves in any arbitrary shapes having a plurality of air outlet ports at the inside bottoms thereof is integrally made on the front sole area, and a larger density and anti-compressive foam pad is distributingly punched with several small holes while the unpressed arch area of foot is densely punched with several big holes, whereby through said structure, air flow and air change effects are significantly strengthened.
(b) Description of the Prior Art
A ventilating insole has a air bladder, wherein the top insole above the air bladder is made with an air inlet port at heel area thereof, and made with several air outlet ports at the front sole area thereof.
Prior patents for ventilating insole can be referred to U.S. Pat. No. 4,215,492, Aug. 5, 1980; U.S. Pat. No. 5,010,661, May 30, 1991; U.S. Pat. No. 5,333,397, Aug. 2, 1994; U.S. Pat. No. 4,224,746, Sep. 30, 1980; WO 97/04676A1, Feb. 13, 1997; and China Utility Model patent No. 925176, Jul. 18, 2007, etc.
Prior patents for insole internal air bladder to be insertingly installed with foam pad (or sponge pad) can be referred to U.S. Pat. No. 4,224,746, Sep. 30, 1980; U.S. Pat. No. 6,006,447, Dec. 28, 1999; WO 97/04676A1; and China Utility Model patent No. 925176, Jul. 18, 2007, etc.
However, regarding known ventilating insole structure on the streets and in the prior patents, if the top insole is made to a level plane, then when the foot is raised above ground, air inlet ports are easily covered by heel of the foot for a tight shoe, so air is difficult to flow in air bladder through said air inlet ports; on the other hand, when the insole is pressed by the foot, if the air outlet ports are covered by front sole of the foot, air inside air bladder is difficult to flow out from the air outlet ports, thereby the imperfections of unsmooth air flow are commonly found in everywhere.
In addition, if said air bladder of ventilating insole structure is constituted by the top and bottom insoles and a middle foam pad, wherein if the foam pad with large porosity and low density is used, although it has a larger air volume, it is easily squelched due to elastic fatigue, on the contrary, if a foam pad with small porosity and larger density is used, although it is advantageous to have a good elasticity and therefore is not easily squelched, however, its air flow is unsmooth due to smaller air volume and there is other imperfections such as heat source generated by impingement and friction when air is flowed through the larger density foam pad.